Side-mounted derrick for tractors



Dec. 25, 1934.

'N. M ERDAHL SIDE MOUNTED DERRICK FOR TRACTORS Filed May 12, 1932 5 Sheets-Sheet l N. M. ERDAHL 1,985,285 SIDE MOUNTED DERRICK FOR TRACTORS' 5 Sheets-Sheet 2 Dec. 25, 1934.,

N. M. ERDAHL SIDE MOUNTED DERRICK 1 0R TRACTORS Dec. 25, 1934 Filed May 12', 1932 5 Sheets-Sheet 5 zzsmzzmeys.

and provided with counter-weight means at the v as H l mming-25. 1 I I I UNiTEo TATESIffPATEN SIDE-MOUNTED DERRICK ACTORS Highway Trailer Company, Edger-ton, Wis a corporation 01' Wisconsin Application my 12, 1932, No. 610,850

4 Claims. (01. 212-49) This invention relates to portable derricks, and radiator, 6, disposed at one end'oi such housing, for purposes'oi illustration the means shown for. and with suitable gearing not shown in detail, 'artransporting the derrick is in the form of a ranged for connecting the engine with the crawlcrawler tractor, inasmuch as this type of vehicle er chains, 1, 1, for driving the vehicle- A lonfurnishes a rather stable form of base, and is gitudinal frame member, 10, extending from the 5 itself, adaptable to various heavy duty jobs which wheel, 2, to the wheel, 3, on one side of the veirequently arise in connection with the useot hicle and serving also as a mounting means for portable derricks' and hoisting machinery. One the idlers, 4, provides support for aspecial bracket object of the invention is ,to further increase-the plate, '7, having lugs, 8, to which the lower ends stability of the carrying vehicle by providing of the boom structurearepivoted. The boom, as '10 means for counter-weighting the vehicle on the shown in Figure 5, consists of two side chanside opposite to that from which the derrick boom nels, 9, 9, disposed in non-parallel relation and extends. Another object is to arrange such converging to a'terminal or head block which counter-weight means adjustably so that it'may includes ears, 11, to which .the sheave or pulley be collapsed or folded substantially within the block, 12, is pivoted at 11*.- .A bill or extension 15 normal outlines of the vehicle for travel. A i'urconsisting oi two plate portions, 13,-ext'ends transther object is to provide the derrick booth with versely of the channels, 9,inthe opposite-direction an adjustable post or ioot-piecewhich may be from the cars, 11, and supports a cross pin, 14, employed in some situations for stabilizing thefrom which the pulley block, l5,is suspended by entire apparatus when it is lifting. unusually' a clevis, 16. Said bill at its outer end is pro-- heavy loads. The invention is also directedto vided with asecond cross'pin at 17 for engagement improvements in the design and'mode oi! conwith the upper end or the auxiliary supporting struction of the boom and supporting structure post or leg, 18, seen in Figure 3. This leg inthereiorwhich adapts the tractor for carrying it, cludes a lower portion and an upper portion, 18, and provides for driving the derrick-operating telescopically engaged in the lower-portion and cables by means of the same power plant which adjustable to diflerent lengths by the insertion of propels the tractor for travel. The invention the cross pin, 19, at one of the several holes, 20, thus consists of various features and elements of provided for this purpose in the lower hollow construction in combination, as herein shown and member of the leg. The boom is strongly reindescribed, and as indicated by the claims. forced by means 0! ,a structural X .at 21, cross In the drawings: w I members, 22 and 23. and asubnantially V-shaped- Figure 1 is a side elevation 01' a tractor fitted bracing mem P C at the Wide end of with a derrick in accordance with thisinvention, the'boom just below the cross member, 23. All

bracing members are electrically welded in position, thus forming the boom into a substantially v unitary structure of great rigidity.

.Forsupporting the boom and its operating cables, I provide the tractor with a special iramework consisting otan arched structure'ior supporting the winding drums, 25, directly over one 40 of the crawler chains, 1, and a bracing structure'extending fromsaid arched structure across the tractor to an anchorage. adjacent the other crawler chain. 1. The arch structure includes a pair of uprights, 26, supported by laterally ex- 4 -tending brackets, 27, which rest upon the horizontal frame member, 28, and these uprights are bent-inwardly ,at 29 for connection with'cross members, 30, extending transversely over the crawler chain, 1, to the inner uprights, 31, which reach down to the side members 32, ofthe main frame of the vehicle for their support and anside shown in this view.

Figure 2 is an elevation of the other side 01' a tractor, being the side at which the derrick boom is carried. I I Figure 3 is a front elevation showing the apparatus adiusted with the boom extended, and with the auxiliary supporting post in position, and also showing the counter-weight partly extended.

Figure 4 is a top plan view of the tractor showing the counter-weightiully extended, and showing a portion of the boom in extended position.

Figure 5 t a detail plan view of the boom.

Figure 6 is a detail section taken as indicated at line 66 on Figure 4 for-indicating the construction of the counter-weight units.

The crawler tractor shown in thefdrawings is of a standard type, including a pair of crawler chains, 1, carried on the usual sprockets, 2 and 3, with idler wheels, 4, adjacent the road-engaging chorage. A platform 33, is carried by andIbeply of each chain. The engine is located within tween the uprights, 26 and 31, for mounting the a hood or housing indicated at 5, with the usual winding drums indicated at 25. w

The bracing structure consists of a Y-shaped frame having plate members,- 34, 34, extending over the engine hood, 5, from their connection to the uprights, 31, and converging as viewed in plan. These plates are spliced to parallel plate members, 35, 35, secured together with suitable spacers between them, and furnishing support for pulleys, 36, 37 and 38, overwhich is trained the hoisting cable, 40 extending from one of the drums at 25 to the pulley block 15, and its associated pulley block, 39, which carries the load hook, 41, as seen in Figure 3. The lower end of the bracing frame is riveted to bracket lugs, 42, extending outwardly from the same bracket plate, 7, to which the boom is fulcrumed.

The raising and lowering of the boom itself is accomplished by means of a cable, 45, extending from a second winding drum, 25 and trained through the sheave block, 12, and the block, 44, attached respectively to the boom and to suitable lugs,.43, of the arched framework. It will be understood that the movement of the derrick may be controlled by any suitable clutch mechanism for driving the drums, 25 and 25, at will, and in either direction, for reeling or unreeling the cables, 40 and 45, respectively, in the usual manner. In view of the strain imposed upon the bracing structure by the operation of the cable, 40, over the pulley, 36, the transversely extending plates, 34, may be reinforced by uprights, 46, having footing upon the longitudinal member of the tractor frame, 32, at that side of the vehicle, and preferably. these uprights, 46, diverge from their connection to the plates, 34, to afford a bracing effect in a longitudinal vertical plane.

The counter-weight structure for balancing the lifting effort of the boom consists of a pair of arms, 50, which are hingedly connected to the brackets, 27, at 51, and which stand in' vertical position just outside one of the crawler chains, 1, when'adjusted for travel of the tractor vehicle. These arms, 50, are transversely conne'ct-' ed by cross bars, 52 and 53, between which a series of counter-weight units, 54, of cast iron -or steel are removably held. To the ends of the cross bar, 52, a pair of hoisting cables, 55, are attached, and extend over pulleys, 56, which may serve as winding drums for paying out or reeling in the cables, 55, to lower or raisethe counterweight frame so as to extend it and its weights, 54, more or less from the side of the tractor. The pulleys, 56, need only berather deeply grooved to serve this purpose, since two or three turns will be sufficient for adjusting the counter-weight frame from one limit to the other. Any suitable driving connection may be provided for the pulleys, 56; the drawings show a chain drive at 57, extending to a shaft, 58, associated with the drums, 25 and 25, but if preferred, a hand-operated worm may be provided for operating the pulleys, 56, and the counter-weight frame. When the boom is raised to its vertical position for travel it may come up rather quickly under the engine power, and to a oid shock to the framing I provide one or more bumper springs shown at 60 in Figure 3 to arrest this movement.

Iclaim: 1, In combination, a vehicle, a derrick boom mounted thereon and adjustable to extend later- "ally'beyond the ground-engaging base of the vehicle, and a counter-weight fulcrumed on a horizontalaxis at one side of the vehicle and extending upwardly therefrom but, adapted to swing outwardly about said axis for extension in the opposite direction from the boom, said counter-weight being relatively thin in the direction of its swinging movement, so that when folded up against the side of the vehicle said counter-weight and parts associated directly therewith extend laterally from the vehicle by a relatively small amount. v

2. In combination with a crawler tractor comprising a power plant, a supporting frame therefor, and a pair of crawler chains disposed respectively at opposite sides of the power plant with a frame for each of said chains connected to the first mentioned frame, a derrick boom, and means for mounting it comprising a frame structure formed to stand astride the tractor power plant extending closely thereover, and including a footing on each of the crawler frames, fulcrum means for the derrick boom disposed closely adjacent the footing of said structure on one of the crawler frames and below the upper ply of the crawler chain, winch mechanism carried by the frame structure over the other crawler, and guide pulleys journaled insaid frame structure, arrangedcfor leading a hoisting cable from the winch mechanism over the power plant and thence downwardly adjacent the fulcrum of the boom for extension along said boom to a pulley near its outer end.

3. In combination with a crawler tractor comprising a power plant, a supporting frame therefor, and a pair of crawler chains disposed respectively at opposite sides of the power plant with a frame for each of said chains connected to the first mentioned frame, a derrick boom, and means for mounting it comprising a frame structure formed to stand astride the tractor power plant extending closely thereover, and including a footing on each of the crawler frames, fulcrum means for the derrick boom disposed closely adjacent the footing of said structure on one of the crawler frames and below the upper ply of the crawler chain, winch mechanism carried by the frame structure over the other crawler, said boom comprising a pair of side members spaced apart at the fulcrum of the boom, and said frame structure comprising members widely spaced fore-and-aft of the tractor for their connection to one of the crawler frames and con--v verging in the portion of the structure which extends over the power plant so that said members are closely spaced above and adjacent the other crawler frame, guide pulleys supported between said members and arranged for leading the power plant, thence downwardly between said closely spaced members to a pulley substantially at the axis of the derrick fulcrum, whereby said cable extends laterally from the tractor at a point near the ground.

4. In combination with a crawler tractor comprising a power plant, a supporting frame therefor, and a pair of crawler chains disposed respectively at opposite sides of the power plant with a frame for each of said chains connected to the first mentioned frame, a derrick boom, and means for mounting it comprising a frame structure formed to stand astride the tractor power plant, and including a footing on each of the crawler frames from which said frame struc footing oi. said frame structure and between two rection of its swinging movement .so that when vertical members of said structure which are folded up in vertical position against the side spaced apart longitudinally of the vehicle, said of the vehicle. its lateral extent is not substancounterweight beinz'lthus adapted to swing euttially greater than that of the vertical members I wardly about its axis for extensionlaterally of of the frame structure between which it stands. 5

the vehicle and being relatively thin in the di- NICHOLAI M. ERDAHL. 

